JP4278142B2 - Communication system, gateway device, and access point device - Google Patents

Description

  The present invention relates to a communication system such as a telephone (voice communication) and a teleconference system, and more specifically, wireless access between terminals as endpoints in a network in which a plurality of communication methods such as wired LAN, wireless LAN, and Bluetooth are mixed. The present invention relates to a communication system, a gateway device, and an access point device that perform communication via a point or a gateway device.

  A conference terminal that is connected to a wired network and a wireless network and can execute a plurality of communication methods may be installed in a conference room. In this case, there may be many times when the conference terminal is not used, such as when the conference is not held or when the conference terminal is not used in the conference. Further, in recent years, wireless communication functions have been added to office devices such as copiers, printers, and facsimile machines, and apparatuses that can directly print directly from a PC or the like have started to appear. In these office devices, there are not many opportunities to execute wireless communication by print file transfer or the like, and there are cases where wireless communication is not executed. Therefore, it is desired to make it possible to use the above conference terminal and office equipment as network access means in addition to these specific tasks.

As a prior art example, there is one that selects a wireless node to which a user connects based on information such as services that can be provided by the wireless node sent from the wireless node (see, for example, Patent Document 1). There is also a portable wireless desk phone that communicates with a fixed base station that interfaces with a gateway device for connection to an IP network, WAN, or PSTN (see, for example, Patent Document 2).
JP 2000-115173 A JP 2000-183977 A

  However, the invention described in Patent Document 1 can select a wireless node to which a user connects based on information such as services that can be provided by the wireless node sent from the wireless node. It does not describe networks with mixed communication methods. Therefore, when there are a plurality of different wireless system wireless nodes, there is a problem that it may not be possible to connect to a wireless node to which connection is desired.

  The invention described in Patent Document 2 shows a device that combines a gateway function and a wireless access point for connecting to an IP network, WAN, or PSTN, but is connected to a wireless access point on the other end of the connection. There is no way to inquire about the terminal information. Therefore, there is a problem that terminals other than the telephone cannot communicate with each other via a plurality of wireless access points.

  The present invention has been made in view of the above circumstances, and an access point device having a wireless access point function that enables communication between terminals having different network access means and communication methods, a gateway device having a gateway function, and communication Provide a system. These communication apparatuses are provided in a form incorporated in office equipment such as a conference terminal installed in a conference room or a copier installed in an office.

  Further, the present invention inquires terminal information that can be communicated to a communication device having terminal information management means for collecting and storing information of a plurality of terminals, and even when the address of the other party is unknown, the terminal of the endpoint It aims to be able to communicate between each other.

  In addition, the present invention enables communication with each other using a gateway function that converts a protocol of a communication device that is interposed in a communication path even when a plurality of communication methods are executed on a communication path with a partner terminal. For the purpose.

  In addition, the present invention enables communication with each other using an access point function of a communication device interposed in a communication path even when an endpoint terminal has only short-range wireless communication means such as Bluetooth. With the goal.

  In addition, the present invention enables a communication device interposed in a communication path to execute a wireless communication method of each terminal so that they can communicate with each other even when an executable wireless communication method differs depending on an endpoint terminal. Objective.

In order to achieve this object, a communication system of the present invention is a communication system having a first communication device and a second communication device capable of communicating with one or more terminals that have established communication in advance. In response to a request from the first terminal that has established communication, an inquiry is made to the second communication device as to whether there is a terminal that can communicate with the first terminal. The second communication device receives an inquiry from the first communication device, By establishing communication with the above terminals and communicating with one or more second terminals with which communication has been established, a terminal that can communicate with the first terminal is searched from the second terminal, and the second terminal that has been searched for Terminal information related to the first communication device is collected, and when the first communication device receives the terminal information from the second communication device, the first communication device transmits the received terminal information to the first terminal. Features.

In the communication system of the present invention, terminal information is characterized in that the terminal is capable of executing applications.

In the communication system of the present invention, terminal information is characterized by a capability list held by the terminal.

In the communication system of the present invention , the first communication device and the second communication device have a gateway function for performing protocol conversion.

In the communication system of the present invention , the first communication device and the second communication device have an access point function that bridges wireless communication and wired communication.

In the communication system of the present invention , the first communication device and the second communication device can switch and execute a plurality of wireless communication methods.

In the communication system of the present invention , the first communication device and the second communication device can simultaneously execute a plurality of wireless communication methods.

The gateway device of the present invention is used as the first communication device or the second communication device in the communication system of the present invention .

The access point device of the present invention is used as the first communication device or the second communication device in the communication system of the present invention .

  According to the present invention, by using a wireless access point capable of executing a plurality of communication methods and a communication device having a gateway function, communication between various endpoint terminals is possible, and user convenience is improved. . In particular, when the address of the partner terminal is not known, the convenience effect is increased. In addition, since an IP network such as the Internet is used, communication charges can be reduced as compared with the case where a public network such as PSTN, ISDN, or cellular network is used.

  The best mode for carrying out the present invention will be described below in detail with reference to the accompanying drawings.

  The first embodiment is a case where communication is performed via a wireless access point having a gateway function. First, a case will be described in which endpoint terminals that perform short-range wireless communication communicate with each other via two wireless access points having a gateway function.

  A network configuration example in this case is shown in FIG. In FIG. 1, a base A has a PDA (Personal Digital Assistant) 1 and a Bluetooth access point 3 to which an earphone microphone (with an earphone and a microphone built in one device) 2 is connected, and a base B has an earphone microphone 6 There are a PDA 5 and a Bluetooth access point 4 connected to each other. The Bluetooth access point 3 and the Bluetooth access point 4 are connected to a WAN (Wide Area Network) by Ethernet (R), and convert between the Bluetooth protocol and TCP / IP which is a protocol on the Ethernet (R). Function as. The Bluetooth standard is an existing communication method. For example, BNEP (Bluetooth Network Encapsulation Protocol) is used for the upper layer of the link layer L2CAP (Logical Link Control and Adaptation Protocol), and TCP is used for the upper layer of BNEP. There is a personal area network (PAN) profile and a cordless telephone profile that carry communication using TCP / IP.

  The hardware configuration of the Bluetooth access point 3 and the Bluetooth access point 4 is shown in FIG. The Bluetooth access point includes a CPU 30, a clock 31, a UART 32, a Bluetooth module 33, an antenna 34, a main memory 35, a ROM 36, a LAN controller 37, a LAN I / F (Interface) 38, a bus 39, and the like.

  The CPU 30 executes and processes a control processing program, an OS (Operating System), and various application programs stored in a ROM (Read Only Memory) 36.

  The clock 31 includes a crystal oscillator and a frequency divider circuit, and generates a clock for controlling the operation timing of the CPU 30.

  A UART (Universal Asynchronous Receiver Transmitter) 32 is an interface that transmits and receives serial data between the CPU 30 and the Bluetooth module 33, and includes a FIFO (First In, First Out), a shift register, and the like.

  The Bluetooth module 33 includes an RF unit and a baseband unit, and executes wireless communication in conformity with the Bluetooth standard.

  The main memory 35 is composed of a DRAM (Dynamic Random Access Memory), and is used in a work area of the CPU 30 or the like.

  In the ROM 36, a program for controlling the operation of the Bluetooth access points 3 and 4 is written in advance. The LAN controller 37 executes a communication protocol compliant with, for example, the IEEE (Institute of Electrical and Electronics Engineers) 802.3 standard, and communicates with other devices connected to the Ethernet (R) via the LAN I / F 38. To control.

  PDA1 and PDA5 implement Bluetooth as a communication means, and Bluetooth executable profiles are a PAN profile and a cordless telephone profile. The Bluetooth access point 3 and the Bluetooth access point 4 can also execute a Bluetooth PAN profile and a cordless telephone profile.

  FIG. 2 shows the protocol configuration of the Bluetooth PAN profile, and FIG. 3 shows the protocol configuration of the cordless telephone profile. 2 and 3, SDP is Service Discovery Protocol, LMP is Link Manager Protocol, and ME is Management Entity. In FIG. 3, TCS is Telephony Control Protocol Specification, which establishes telephone connection and voice channel. The ACL in the baseband is an Asynchronous Connection-Less link, and the SCO is a Synchronous Connection-Oriented link. Voice data is transmitted and received with the application using this SCO link.

  When the Bluetooth PAN profile is executed, the Bluetooth access point 3 and the Bluetooth access point 4 cut out protocol data located above the BNEP from the data received by Bluetooth communication, that is, TCP / IP data, and send it to the Ethernet (R) . Further, protocol data located below BNEP is added to the TCP / IP data received from the Ethernet (R), and further transmitted as an RF signal.

  In addition, when the Bluetooth access point 3 and the Bluetooth access point 4 execute the Bluetooth cordless telephone profile, the voice data received by the Bluetooth communication is put in a UDP / IP packet and transmitted to the Ethernet (R), and the Ethernet (R). For the UDP / IP voice data received from, the voice data is cut out from the UDP / IP packet and transmitted as an RF signal.

  Next, there are a plurality of terminals that can communicate with the Bluetooth access point 4 at the base B, and the PDA 1 at the base A inquires of the Bluetooth access point 4 whether there is a terminal that can perform voice communication, and the Bluetooth access point 4 Will return the terminal information capable of voice communication, and the procedure until the PDA 1 can perform voice communication with the terminal desired by the site B by this terminal information will be described. FIG. 4 shows a device that can perform Bluetooth communication at the base B.

  Base B has one PDA and two notebook PCs. Two notebook PCs are equipped with a Bluetooth PC card (PCMCIA card), and the Bluetooth PAN profile can be executed. The PDA 1 at the site A has already established a link (LMP and L2CAP) with the Bluetooth access point 3 and can perform communication by TCS. (The LMP establishment procedure will be described later.) When the PDA 1 designates the address (IP address) of the Bluetooth access point 4 by the user and performs an operation for inquiring the Bluetooth access point 4 about a terminal capable of voice communication, The CL INFO, which is a TCS connectionless message, includes the IP address of the Bluetooth access point 4 and the inquiry command of the voice communicable terminal (set in the company specific information element of the CL INFO) and transmits it to the Bluetooth access point 3.

  Upon receiving this message, the Bluetooth access point 3 transmits an inquiry command for a terminal capable of voice communication to the Bluetooth access point 4 using the HTTP (HyperText Transfer Protocol) protocol. When receiving this command, the Bluetooth access point 4 checks whether there is a terminal capable of voice communication by the Bluetooth procedure described below.

First, all slave terminals that can communicate with the Bluetooth access point 4 (master) are recognized by the inquiry procedure. That is, the Bluetooth access point 4 repeatedly transmits the ID packet, and the slave terminal that receives the ID packet transmits an FHS packet including the Bluetooth device address (BD_ADDR), the system clock of the terminal itself, and the like. The Bluetooth access point 4 recognizes the number of slave terminals from the number of received FHS packets (the number of BD_ADDR). For example, in the case shown in FIG. 4, three slave terminals are recognized.
Next, the Bluetooth access point 4 sequentially establishes communication connections with the three slave terminals. The communication connection establishment procedure will be described. The Bluetooth access point 4 transmits an ID packet including a synchronization word derived from LAP (Lower Address Part) which is a lower address part of BD_ADDR received from the slave terminal. When the slave terminal receives the ID packet including the synchronization word derived from the BD_ADDR of the own terminal, the slave terminal responds with the ID packet. Next, the Bluetooth access point 4 transmits an FHS packet in which 1 is set in the active member address (AM_ADDR) which is the identification number of the slave terminal. When the slave terminal receives this, it responds with an ID packet. At this time, the slave terminal switches to the system clock of the Bluetooth access point 4 included in the FHS packet. Next, the Bluetooth access point 4 transmits a POLL packet, and the slave terminal responds with a NULL packet to establish a baseband layer connection.

  Subsequently, the Bluetooth access point 4 and the slave terminal move to a connection establishment sequence between the link manager and the link manager. The Bluetooth access point 4 transmits an LMP_host_connection_req PDU (Protocol Data Unit), and the slave terminal responds with an LMP_accepted PDU.

  Next, the Bluetooth access point 4 transmits an LMP_features_req PDU, and the slave terminal responds with an LMP_features_res PDU and exchanges information about the function of the terminal itself. Next, the Bluetooth access point 4 transmits an LMP_setup_complete PDU, and the slave terminal responds with the LMP_setup_complete PDU to establish a link-manager (link layer) connection.

Subsequently, the Bluetooth access point 4 executes a service discovery sequence. When the application of the Bluetooth access point 4 issues a service discovery request to the SDP task, the SDP task first issues a connection request for an SDP connection (L2CA_ConnectReq event) to the L2CAP task. When the L2CAP task receives this request, it transmits a Connection Request packet. When the L2CAP task of the slave terminal receives this packet, it passes an L2CA_ConnectInd message to the SDP task and responds with a Connection Response packet to the master terminal to establish an SDP connection.

  Subsequently, the SDP task issues a configuration request (L2CA_ConfigReq event) to the L2CAP task. Upon receiving this request, the L2CAP task transmits a Configuration Request packet including configuration parameters such as quality of service (QoS). When the L2CAP task of the slave terminal receives this packet, it passes an L2CA_ConfigInd message to the SDP task and responds to the Bluetooth access point 4 with a Configuration Response packet including configuration parameters.

  Next, an SDP_ServiceSearchRequest PDU including a UUID (service unique identifier) indicating that the SDP task of the Bluetooth access point 4 is a telephone is included in the ServiceSearchPattern parameter. If the slave terminal can execute the telephone service, this SDP task Responds with an SDP_ServiceSearchResponse PDU.

  The procedure up to the service discovery sequence between the Bluetooth access point 4 and one slave terminal (for example, the PDA 5) has been described above, but the same applies to other slave terminals (the notebook PC 10 and the notebook PC 11) sequentially. Follow the steps. Note that the notebook PC 10 and the notebook PC 11 do not respond with an SDP_ServiceSearchResponse PDU because there is no telephone service.

  In this way, the Bluetooth access point 4 detects the PDA 5 as a terminal capable of performing telephone communication. Then, the Bluetooth access point 4 transmits information of the PDA 5 as a terminal capable of voice communication to the Bluetooth access point 3, for example, a friendly name (name of owner, etc.) registered by the user to the terminal. This friendly name can be received from the PDA 5 during the inquiry procedure described above. This PDA 5 information is transmitted using the HTTP protocol. When the Bluetooth access point 3 receives the information of the PDA 5, it transmits this information to the PDA 1 in the company specific information element of the CL INFO message. The PDA 1 displays the name of the received PDA 5 on the display, and when the user of the PDA 1 wishes to perform telephone communication with the user of the PDA 5, the name of the PDA 5 is selected and a call button displayed on the display is pressed. The subsequent connection procedure from PDA1 to PDA5 is as follows.

  First, the PDA 1 places the IP address of the Bluetooth access point 4 and the name of the PDA 5 in the company specific information element of the Setup message and makes a call connection to the Bluetooth access point 3. Next, the Bluetooth access point 3 sends an ITU-T recommendation H.264 to the Bluetooth access point 4. A call is made according to H.323. The name of the PDA 5 and the call request information to the PDA 5 are H.264. It is included in the UUI (User User Information) of the Setup message, which is a H.323 call message. When the Bluetooth access point 4 receives this Setup message, it makes a telephone call to the PDA 5 using the Bluetooth TCS. When the PDA 5 responds, the Bluetooth access point 4 returns a response message (Connect message) to the Setup message to the Bluetooth access point 3, and a connection between the Bluetooth access point 3 and the Bluetooth access point 4 is established. A voice channel is further opened between the points, and telephone communication can be executed between the PDA 1 and the PDA 5. At this time, voice data is transmitted / received between the PDA 1 and the Bluetooth access point 3 and between the PDA 5 and the Bluetooth access point 4 through the baseband SCO link.

  A schematic operation flow of the PDA 1 is shown in FIG. 7, and a schematic operation flow of the Bluetooth access point 4 is shown in FIG.

  As shown in FIG. 7, the PDA 1 confirms whether or not the user has made an operation for inquiring a terminal capable of voice communication to the Bluetooth access point 4 (S11). When there is an inquiry operation, a CLIINFO message including the IP address of the Bluetooth access point 4 and an inquiry command of a terminal capable of voice communication is transmitted (S12). And the information of PDA5 is received (S13) and the name of PDA5 is displayed on a display (S14). Next, it is confirmed whether or not the user has made a call request operation to the PDA 5 (S15). Then, a Setup message including the IP address of the Bluetooth access point 4 and the name of the PDA 5 is transmitted to connect to the Bluetooth access point 3 (S16). Next, voice data is transmitted and received through the baseband SCO link (S17).

  As shown in FIG. 8, first, the Bluetooth access point 4 confirms whether an inquiry command for a terminal capable of telephone communication has been received (S21). The name of the terminal capable of Bluetooth communication is acquired by the inquiry procedure (S22). A terminal (PDA5) capable of telephone communication is detected by service discovery by sequentially connecting to each Bluetooth terminal (S23). The terminal name acquired from the telephone communicable terminal is transmitted to the Bluetooth access point 3 (S24). Next, H.I. It is confirmed whether the 323 Setup message has been received (S25). A telephone connection is made to the PDA 5 using Bluetooth TCS (S26). Then, a Connect message is transmitted to the Bluetooth access point 3, and voice data is transmitted and received through the established voice channel (S27). Next, voice data is transmitted and received through the PDA 5 and the baseband SCO link (S28).

  In the above embodiment, a case where telephone communication is executed is shown. However, when there is a notebook PC capable of executing a Bluetooth PAN profile at the site A, the access point 4 at the site B is replaced with a telephone communication terminal. The notebook PC at site A can execute data communication with the notebook PC at site B using the PAN profile by the same procedure as described above. This detailed description is omitted.

  The second embodiment is a case where communication is performed via a wireless access point that executes a plurality of wireless communication methods.

  In the first embodiment, a Bluetooth access point is described as an example of a wireless access point. In the second embodiment, a case where both Bluetooth and IEEE802.11a wireless LAN communication can be executed as a wireless access point will be described. . IEEE802.11a uses OFDM (Orthogonal Frequency Division Multiplexing) as a modulation method and CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance) as a MAC (Media Access Control) layer. The transmission rate is 36 to 54 Mbps, and 5.15 G to 5.25 GHz is allocated in Japan.

  In this embodiment, as shown in FIG. 5, there is a wireless access point that can execute communication of both a single PDA and two notebook PCs and Bluetooth and IEEE802.11a wireless LAN at the base A. There is a wireless access point capable of executing communication of both a single PDA and two notebook PCs and a wireless LAN of Bluetooth and IEEE802.11a. The PDAs existing at the bases A and B can execute telephone communication by Bluetooth, and all the notebook PCs existing at the bases A and B are equipped with IEEE802.11a wireless LAN cards (PCMCIA cards). .11a wireless communication is executable. All the notebook PCs existing at the base A and the base B acquire an IP address from the DHCP server.

  FIG. 9 shows the hardware configuration of the wireless access points 22 and 25 existing at the site A and the site B. The wireless access point includes a CPU 30, a clock 31, a UART 32, a Bluetooth module 33, an antenna 34, a main memory 35, a ROM 36, a LAN controller 37, a LAN I / F (Interface) 38, a bus 39, a wireless LAN controller 40, an antenna 41, and the like. It is configured. The components other than the wireless LAN controller 40 and the antenna 41 are the same as those shown in FIG. The wireless LAN controller 40 executes communication conforming to the IEEE802.11a wireless LAN standard.

  In the case of Bluetooth, the wireless access points 22 and 25 collect friendly names registered in the terminal by the inquiry procedure shown in the first embodiment. In the case of a wireless LAN, terminal information is collected by UPnP (Universal Plug and Play). UPnP is a standard that can detect a device on a network and know the services that the device can provide. This standard is created by the UPnP Forum. When the wireless access point detects a terminal on the wireless network using UPnP, the wireless access point obtains the device description of the terminal. This device description includes a model name (product name) of the terminal, a manufacturer name, a list of services and functions that can be provided by the terminal. The protocol used at this time is HTTP by UDP multicast for terminal detection (discovery), and HTTP (the lower protocol is TCP / IP) for obtaining a device description. The obtained terminal information is stored in association with the IP address of the terminal (obtained from the header of the received IP packet).

  The PDA 20 at the site A executes the same procedure as in the first embodiment, and performs voice communication with the PDA 26 at the site B. An operation when the user of the PDA 20 at the site A transmits a file stored in the notebook PC 23 to the notebook PC 29 at the site B will be described.

  The user A of the PDA 20 at the site A communicates with the user B of the PDA 26 at the site B by transferring files to the notebook PC 29 using NetMeeting (call connection protocol using ITU-T recommendation H.323) made by Microsoft. Inform. User B starts NetMeeting on the notebook PC 29. By the operation of the user A, the notebook PC 23 transmits a terminal information inquiry command to the wireless access point 25 at the base B via the wireless access point 22 using the HTTP protocol. The wireless access point 25 returns the collected terminal information and the IP address of the terminal using the HTTP protocol, and the notebook PC 23 displays the received terminal information as a list together with the IP address. Here, the user A knows the information regarding the terminal of the notebook PC 29 from the user B through conversation, and specifies the notebook PC 29 from the displayed terminal information list. Next, the user A activates NetMeeting on the notebook PC 23 and inputs the IP address of the identified terminal (notebook PC 29) as a destination to perform a connection operation. The notebook PC 23 and the notebook PC 29 are first connected in the voice communication mode (essential in NetMeeting), and then the user A transmits a file to the notebook PC 29 using the NetMeeting file transfer function.

  In this way, wireless communication between the wireless terminals existing at the base A and the base B can be executed simultaneously. Note that the wireless access point 22 and the wireless access point 25 may process Bluetooth and IEEE802.11a wireless LAN operations in parallel, or may switch and process them at predetermined time intervals. This detailed description is omitted. In addition, the wireless access point 22 and the wireless access point 25 can perform data communication only with the HTTP port, the voice communication port, and the file transfer port, and can improve security by closing other ports. .

  The Bluetooth access point and the wireless access point shown in the above embodiments can be incorporated in a network compatible copying machine, printer, facsimile machine or the like.

  As mentioned above, although the Example of this invention was described, it is not limited to the said Example, A various deformation | transformation is possible in the range which does not deviate from the summary.

  The present invention can be applied to a copying machine, a printer, and a facsimile apparatus having a wireless access point function and a gateway function.

It is the schematic which shows the network structural example which is an Example of this invention. It is a figure which shows the protocol structure of a PAN profile. It is a figure which shows the protocol structure of a cordless telephone profile. It is the schematic which shows the network structural example of Example 1 of this invention. It is the schematic which shows the network structural example of Example 2 of this invention. It is a block diagram which shows the hardware constitutions of a Bluetooth access point. It is a flowchart which shows the processing operation of PDA. It is a flowchart which shows the processing operation of a Bluetooth access point. It is a block diagram which shows the hardware constitutions of a wireless access point.

Explanation of symbols

1, 5, 20, 26 PDA
2, 6, 21, 27 Earphone microphone 3, 4 Bluetooth access point 10, 11, 23, 24, 28, 29 Notebook PC
22, 25 Wireless access point 30 CPU
31 clock 32 UART
33 Bluetooth module 34, 41 Antenna 35 Main memory 36 ROM
37 LAN controller 38 LAN I / F
39 Bus 40 Wireless LAN controller

Claims (9)

A communication system having a first communication device and a second communication device capable of communicating with one or more terminals that have established communication in advance,
The first communication device is
Inquiries to the second communication device as to whether there is a terminal capable of communicating with the first terminal by a request from the first terminal that has established communication;
The second communication device is
After receiving an inquiry from the first communication device, the terminal establishes communication with one or more terminals, and communicates with one or more second terminals with which communication has been established. Searching from the second terminal, collecting terminal information related to the searched second terminal, sending the collected terminal information to the first communication device,
The first communication device is
When the terminal information is received from the second communication device, the received terminal information is transmitted to the first terminal . The terminal information, the communication system according to claim 1, wherein the said terminal is a viable application. The terminal information, the communication system according to claim 1, characterized in that the capability list held by the terminal. The first communication device and the second communication apparatus, a communication system according to any one of claims 1 to 3, characterized by having a gateway function for converting a protocol. The first communication device and the second communication apparatus, a communication system according to item 1 any one of claims 1 to 3, characterized in that with an access point function for bridging a wireless communication and wired communication. The communication system according to claim 5, wherein the first communication device and the second communication device can switch and execute a plurality of wireless communication methods. The communication system according to claim 5, wherein the first communication device and the second communication device can simultaneously execute a plurality of wireless communication methods. The gateway apparatus characterized by being used as a 1st communication apparatus or a 2nd communication apparatus in the communication system of any one of Claim 1 to 7 . An access point device used as the first communication device or the second communication device in the communication system according to any one of claims 1 to 7 .

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